This Center of Excellence in Public Health Informatics will be a partnership of three principal entities: the Harvard Medical School/Harvard Pilgrim Health Care Department of Ambulatory Care and Prevention, the Harvard-MIT-Children's Hospital Boston Informatics Program, and the Massachusetts Department of Public Health. The Center has expertise in design and use of Electronic Medical Records (EMRs), Personally Controlled Health Records (PCHRs), and electronic public health reporting and communication systems. The center will link these disparate systems by developing scalable information infrastructures to enable information exchange between individuals, health care providers and public health authorities. During the initial funding period, the Center will conduct two projects that build on existing infrastructure to enhance communications to improve public health practices. Both will yield products that can be widely disseminated and readily adopted. This work will be informed by collaboration with a statewide regional health information organization (RHIO). The Center will create a new software solution, Electronic medical record Support for Public health practice (ESP). ESP will leverage existing data in EMRs by providing secure, PHIN and HIPAA compliant communications between clinicians and public health authorities. ESP will initiate reporting to public health authorities when data entered into EMRs meet criteria for reportable conditions. ESP will also receive and respond to electronic queries from public health authorities when additional clinical information is required for laboratory reported cases. ESP will also include new statistical methods for identifying spatio-temporal dusters from data residing in EMRs. Although initially focusing on STDs and asthma, ESP will address the broad range of reportable conditions of interest to public health authorities. It will be designed as a scalable, configurable system to work with a wide array of EMRs and health department information systems. The Center will also enhance the capabilities of PCHRs to add bi-directional communications between individuals and public health authorities to the PCHRs'existing communications capabilities between individuals and providers. These new capabilities will allow collection of specific risk information and the delivery of highly customized advice regarding specific recommended actions. Although these capabilities will be applicable to a wide range of health conditions, the initial focus will be on improving influenza immunization rates in high-risk populations. There will be a bi-directional link with a state immunization registry. The utility of this system will be demonstrated through its successful deployment in a large health plan that includes both technology rich and poor practices. In addition, the Center will assume a leadership role in public health informatics by participating in national and regional informatics initiatives, through training programs and other scholarly academic activities.